Microwave irradiation of rats at 2.45 GHz activates pinocytotic-like uptake of tracer by capillary endothelial cells of cerebral cortex.
Far-field exposures of male albino rats to 2.45-GHz microwaves (10-microseconds pulses, 100 pps) at a low average power density (10 mW/cm2; SAR approximately 2 W/kg) and short durations (30-120 min) resulted in increased uptakes of tracer through the blood-brain barrier (BBB). The uptake of systemically administered rhodamine-ferritin complex by capillary endothelial cells (CECs) of the cerebral cortex was dependent on power density and on duration of exposure. At 5 mW/cm2, for example, a 15-min exposure had no effect. Near-complete blockade of uptake resulted when rats were treated before exposure to microwaves with a single dose of colchicine, which inhibits microtubular function. A pinocytotic-like mechanism is presumed responsible for the microwave-induced increase in BBB permeability.
Neubauer
C
C
Department of Anesthesiology and Critical Care Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21205.
Phelan
A M
AM
Kues
H
H
Lange
D G
DG
D000818:Animals; D001812:Blood-Brain Barrier / Q000528:radiation effects*; D002199:Capillary Permeability / Q000528:radiation effects*; D008297:Male; D008872:Microwaves; D010873:Pinocytosis / Q000502:physiology* / Q000528:radiation effects; D051381:Rats; D011919:Rats, Inbred Strains